Avatar CGI Bubble Simulation Explained
In Avatar: The Way of Water, the stunning underwater scenes rely on advanced CGI to make bubbles look completely real. Wētā FX, the visual effects team behind the film, spent years perfecting how bubbles form, move, and interact with water and light. This bubble simulation is a key part of what makes Pandora’s oceans feel alive on screen.
Bubbles in the movie start from simple physics rules coded into software. Air gets trapped in water, rises due to being lighter, and breaks apart or merges based on speed and pressure. Wētā FX built custom tools to simulate these behaviors shot by shot. For example, when characters swim fast, bubbles trail behind them in realistic streams, twisting with currents. Slow scenes show tiny bubbles clinging to skin or gear before popping free.
To get this right, the team filmed real actors underwater during performance capture. Divers and high-speed cameras caught actual bubble patterns. These videos fed into the CGI system, training it to match reality. The software then handles millions of bubbles at once, each one unique in size, shape, and path. Light plays a big role too. Sunlight filters through water, refracting off bubble surfaces to create shimmering effects that change with depth.
Complex scenes mix bubbles with sea creatures and wreckage. During action sequences, explosions release huge bubble clouds that swirl chaotically. Wētā FX’s new simulation tech predicts how these masses behave under force, avoiding fake or repetitive looks. Rendering takes hours per frame on powerful computers, balancing detail with smooth motion.
This work pushed CGI forward. Over 3,200 effects shots feature these bubbles, making every dive into Pandora’s seas believable. The result blends human motion, creature designs, and fluid dynamics into one seamless world.
Sources
https://www.youtube.com/watch?v=ANmawvbOpCY
https://www.wetafx.co.nz/
